1. Field of the Invention
This invention relates to a new fuel control system for a gas furnace or the like and as to a new method of making such a system.
2. Prior Art Statement
It is known to provide a control means for a gas furnace that has an electrically operable pilot gas valve means and an electrically operable main gas valve means, the control means comprising an electrical circuit means adapted to be interconnected to a source of alternating current so as to have alternating half wave cycles of one polarity and half wave cycles of the opposite polarity, the circuit means having a flame sense section and a main gas valve means section, the main gas valve means section comprising a main relay coil means which when energized by the circuit means is adapted to operate the main gas valve means to direct main gas to the furnace, the flame sense section comprising a control unit that is adapted to energize the main coil means on each half wave cycle of the one polarity thereof only when a flame sense probe means generates a voltage through flame rectification thereof caused by pilot flame means of said furnace impinging on said probe means. For example, see the Geary U.S. Pat. No. 4,626,192.